GoSlash27

I've been doing some "balance beam" testing with wings, and it seems that the #1 criteria for a "best" wing is lift coefficient to induced drag coefficient ratio. The parasitic drag isn't nil, but it's so much less than induced drag that it's neglible. Likewise, the mass of a wing as pure weight is very little compared to the mass of whatever it's lifting, and can be safely ignored. It's also important to have the correct balance of craft mass to lift coefficient (you don't want too much or too little wing). According to my preliminary results, the delta wing should yield the best results among non-control surfaces. Best, -Slashy

Good point; how much fuel will it take to get to the same point where you start on Kerbin? Once you get to that point, you have to carry the empty tanks for even more DV than from Kerbin. It'll be a chore.

Unfortunately, control surfaces are about the only thing in the proper size range for a lifter this light. I'm going to try a novel concept using a wing, but I'm not hopeful. The parasitic drag is proportional to mass, and wings are massive. I'm pretty sure the difference between making orbit and not is parasitic drag, so...

Shameless battery- hogging (I didn't build it for this challenge), but another confirmation that simpler is better: FWIW it seems that there is an ideal wing area to mass ratio and drag seems to be the most critical factor. Best, -Slashy

Claw, After exhausting the thread, none of the successful attempts were done SSTO without infiniglide. In fact, if it weren't for my shameless battery-hogging, I'd be on the leaderboard with this design. The most successful SSTO attempts consistently had absolute minimum part count for physics parts. Only 2 wings. This gives me an idea...

This would be going by the rocket equation. DV= 9.81 Isp ln(Mw/Md). You need at least 8,500 DV to get from the surface of Eve to LEO. Nothing stock in this game can achieve that, even composed of infinite tanks. Especially not with the t/w demanded for Eve. A chemical rocket to do that job would need an Isp of at least 394 atmospheric. As others have said, if it's possible at all it'll be using an ion glider. Ion engines can make the DV easily, but they lack the t/w to pick themselves up let alone anything else. So it's a glider. unfortunately, gliders are grossly DV inefficient since you spend practically your whole launch fighting drag. Your fuel becomes time. You know exactly how long your engines will provide thrust and how much drag you can push. The question is does a glider exist that is efficient enough to get you to orbit before the clock runs out... How so/what theory?

Sadly, nothing new to report today. I found a lot of new ways to not go to space My record for Kerbin SSTO remains at 1,963. Pretty sure I can get that to orbit, but Eve looks highly unlikely to me.

Negative. The challenge is to get from the surface of Eve to low Eve orbit. - - - Updated - - - Without. Stock parts, stock environment. -Slashy

Nothing new to report today. I found a lot of ways to not go to space

I'm going to bed. Best ascent profile so far is 45* climb. 1,963 m/sec. I'm gonna try varying the lift tomorrow to see what effect (if any) it has.

Yeah... no. Just hold your horses until I make orbit and give you a copy.

After I make orbit (*IF* I make orbit) I will give you a copy of the file and a detailed ascent profile. You will see that infiniglide is not a part of this design. Best, -Slashy

I restarted from baseline with a new design. I tried and tried to make the rudder unnecessary, but no dice. No matter what I did, it was dynamically unstable in yaw. I basically built it backwards so that the drag of the okto 2 would have a stabilizing effect instead of a destabilizing effect, deleted 1 unnecessary control surface, and reverted to the small control surfaces as wings. I think it's under the optimal lift/ weight now, but I'm seeing if it can work as-is. I'm testing different ascent profiles now, and this happened on my third flight. 1,878 M/sec and it was steady as a rock. I think Kerbin SSTO is in the can...

Test run #3 got me 1,877 M/sec. I'm almost there and I haven't made a serious run yet...

I think we need to start this process smaller by first achieving an SSTO ion glider on Kerbin without infiniglide...

I have already beaten that with 2 tanks of xenon and normal fuel flow. I won't divulge too much, but it's *definitely* not an infiniglider. Best run so far was this morning at over 1,800 M/sec. I've started over with a more dynamically stable (and at least on paper more efficient) design. My second ascent profile run has netted 974 m/sec, and I haven't made a serious run yet. Best, -Slashy

^ This. I'm not yet in Kerbin orbit, but I'm very close. The trick seems to be not in getting enough DV, but in making the glider as efficient as possible from a drag standpoint. Lift seems to be a whole lot less critical than drag, and this would be even more true on Eve. I would say that there would be 2 categories here: Unmanned and manned.

I tested a new method for precision deorbiting. Mixed results so far. I also worked on what I hope will be a Kerbin SSTO ion glider... with no wings

No dice. I ain't going' to space tonight. Every time I get near orbital velocity, I lose my longitudinal stability. Perversely, my tail boom seems to be making it worse! I'm reaching the same kinetic energy as earlier tests with a lot more xenon in the tank and good acceleration. Just a matter of fixing the stability issue, I think. I'll try again tomorrow.

I don't think it's mathematically possible either, but I can't prove it. I know that a vertical lift rocket is out of the question, but an ion glider is technically plausible right now. I'm working on an ion glider that looks to be true SSTO from Kerbin if it pans out. If not... I can't say for sure that an Eve SSTO is impossible, but I sure as heck don't know how to do it.

I'm guessing the thicker atmosphere. This vehicle has plenty of excess DV on paper (10,545), but it's almost all wasted due to drag. It's also got way more lift than it needs, so it can climb out quicker in a denser atmosphere. The question is whether it has sufficient DV to do over 9000 m/s without wasting too much time climbing. I gotta pass this test first. Last run was a bust. I got to 30,000 way early, but lost control of the plane. Running it again.

Yessir. Kerbin makes a convenient testbed. My plan is to 1) have an unmanned flight on Kerbin, 2) have a manned flight on Kerbin, 3) have an unmanned flight on Eve, then 4) have a manned flight on Eve. If I can't complete step 1, I'm going to call step 4 impossible. *edit* I just noticed that the nav ball says "orbit". That's a first...

I limited myself to 20 m/sec on the initial climbout to match previous tests, but it wanted to climb. I'm gonna try 40 and see what happens.

Duly noted. We're all wingin' it right now. I *am* a plane guy, but not in KSP. This test was extremely positive, and I think I can top it. 37,034 at 1,611. The big ailerons are an improvement. I'm gonna run it again. / science!

Are you talkin' the drag coefficient or the parasitic drag? That may wreck my plans...